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1991 Dodge Dynasty Repair Question


Topics covered: Transmission, Engine, Sensor.
Mileage: 233,000 miles.

Asked on June 29, 2012

Transmission sensor??

I just bought a 1991 dodge dynasty and the transmission doesn't seem to be shifting out of 3rd gear. I can get up to 55-60 mph but then it redlines. The guy i bought it from said it was a wire going into the transmission that needed to be replaced. Any ides?
Avatar Asked by hortond

Answer

Replied on June 30, 2012

That is called "limp mode" and it allows you to drive slowly to the repair shop without needing a tow truck. Definitely not at 60 mph. It is defaulted to second gear, not third.

There will be a diagnostic fault code stored in the Transmission Computer. Having that read is the place to start. The code will direct you to the circuit or system that needs further diagnosis. You can make some generalizations. If it starts out in second gear as soon as you shift into "drive", it is likely a sensor or some other electrical problem. If it starts out in first gear, then bangs back to second gear during or right after an up-shift, it is usually worn clutch plates or leaking internal seals. The Chrysler scanners and some aftermarket ones will read the "clutch volume index" (CVI). That is a set of four numbers representing the volume of fluid it takes to apply each clutch pack. An experienced transmission mechanic can tell you how much wear is left in each one before a rebuild will be needed.

Tiny Answered by caradiodoc (expert)
17,263 answers provided
Replied on June 30, 2012

Thanks, how much am i looking at for repairs?

Tiny Response from hortond
1 question asked
Replied on June 30, 2012

$25.00 if you replace a sensor yourself to $3000.00 to have the transmission rebuilt at a specialty shop. First you need to find out what's wrong.

Tiny Answered by caradiodoc (expert)
17,263 answers provided

Replied on June 30, 2012

Okay, thanks. Ill get it looked at.

Tiny Response from hortond
1 question asked
Replied on June 30, 2012

Start with the fault codes. Those are stored in the Transmission Computer. Most of the code readers used by the auto parts stores that read codes for you for free only can access the Engine Computer's codes. You need a mechanic with a scanner that will talk to the Transmission Computer.

Also, if the speedometer works properly, the input and output speed sensors should be okay.

Tiny Answered by caradiodoc (expert)
17,263 answers provided
Replied on June 30, 2012

So today i decided to do a tuneup before i took it to the transmission mechanic. After i changed the spark plugs and wires and added fuel injector cleaner to the gas. Now the car will not drive, it starts but as soon as i give it gas to go it dies on me. I didn't mess with anything else and the car ran fine yesterday. Any suggestions?

Tiny Response from hortond
1 question asked

Replied on June 30, 2012

Check for a cracked or disconnected vacuum hose to the MAP sensor. Check if the connector got knocked loose for the throttle position sensor.

Which engine do you have? There's three and they're all different. With a computer-controlled transmission you're going to have the 3.0L or the 3.3L.

Is the Check Engine light on while the engine is running?

Tiny Answered by caradiodoc (expert)
17,263 answers provided
Replied on June 30, 2012

Yeah that hose was cracked and falling to pieces so i disconnected it. The engine is a 3.3L V6. And the Check engine light is not on.

Tiny Response from hortond
1 question asked
Replied on June 30, 2012

Okay, figured out the spark plug wires were in the wrong order. problem solved. but i guess the transmission is stuck in 1st or 2nd gear.

Tiny Response from hortond
1 question asked